The treatment was performed on 13 eyes of 13 patients according to the two standard nomogram �â�� with different radiation power (3 mW and 9 mW) and timing of exposure (30 min and 10 min). UCVA, BCVA, manifest refraction, corneal thickness and endothelial cell density were evaluated before and 1, 3, 6, 12 and 24 months after the procedures. Follow up period was 24 months for all cases. Solution penetration into anterior chamber was checked before the start of irradiation and to its completion (biomicroscopy).

Results:

Before the procedure: UCVA�â��0.06-0.2; K-readers-steep 50.5 D-60.8 D; pachimetry -332�â��402 �Î�¼m, endothelial cell density - 2550-2730 cells/mm2. UCVA slightly decreased during a month after the procedure and returned to initial value or slightly increased at 3 months PostOp. Corneal thickness increased with the application of the hypoosmolar riboflavin solution by �Â�±25.4 �Î�¼m and was reduced by 15-18 �Î�¼m after the procedure. K-readers were flattened by 1-1.5 D, endothelial cells were also slightly decreased (by130-200cells/mm2). Post op period was uneventful, no serious complications observed. At 4-6 months Post Op contact correction with rigid CL were performed on all the eyes.

Conclusions:

Keratoconus treatment with hypoosmolar riboflavin in thin corneas has the same efficacy and safety as standard CXL procedure; it enables to expand indications of CXL. The method enables to stop KC progression, to avoid PK or DALK, gives an excellent opportunity for correction with Rigid Scleral CL after the procedure.